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Thursday, June 29, 2017

Temperature distributions within container

For those interested in heat flow in air, there are some interesting experiments one can build to investigate such flow. These involve trying to determine temperature distributions within containers. A good example of a typical experimental setup, objectives, and analysis can be found here.

Most people would think of getting thermometers and placing them at various locations within a container, but do consider thermistors. These are simple devices that can be purchased from a number of companies online. To use thermistors, you actually measure the electrical resistance, which in turn is converted into temperature via some calibration curve or tables provided with those thermistors. These are also accurate devices, and are quite small so they do not significantly affect the heat flow of your experiment.

Keep in mind that it is possible to model the temperature distribution within containers, as was done in the example paper. A very good, user-friendly piece of software that is designed to solve partial differential equations (as in the diffusion equations for heat flow) is FlexPDE. It always makes for a strong project if theoretical predictions are compared to experimental studies.

Below are a number of ideas for research projects involving temperature distributions within containers:
  • size of the container
  • material from which container is made (makes for a good comparative study)
  • shape of container (same volume, different geometry)
  • location of heat source within the container
  • transparent top with external heat source
  • how heat distribution changes when just filled with air to having varying depths of water or other fluid inside the container
  • time-dependent heat source variation (heat source changing its temperature gradually over time)
  • different materials lining the walls of the container
  • temperature distribution with and without air currents in the container
  • temperature distribution with different objects inside the container: this then opens the door to numerous possibilities, where one could vary the size of the object; the material of the object; the number of objects, and then the distribution of multiple objects within the container
  • one could have multiple containers which are connected with tubing for heat flow between the containers; how does the temperature distribution change over time and space
  • depending on the material from which the container is made, does the external temperature have any effects? For example, if it is a metallic container, does the external temperature change the temperature distribution inside? What if one side sits on ice, and another side has a hot-plate attached?
  • relative humidity variations within the container
  • different air mixtures (with other gases) in the container
  • various objects of different materials within the container; these could be placed inside in symmetric patterns, asymmetric; could be used as barriers; point would be to see how air flow and temperature varies with obstacles/barriers, as well as materials absorbing heat, etc. This allows for large amounts of variation, and original work.

Sunday, June 4, 2017

Drones could lead to all sorts of interesting, and original, local ecological studies!

With the cost of drones decreasing and their popularity soaring, this is good news for high schools and possible research projects and programs for teachers and students! Consider some options that exist now that did not just a couple years ago, and which will likely grab student attention and interest for possible science research projects:
  • Use of drones to study local areas of interest. Could include population studies of different types of animals, land coverage of different local plant species. Interesting studies could include doing this before and after a nearby construction project, and how that affects adjacent ecosystems. This could evolve into longer-term class/program studies, where students do the same counts year after year to measure any changes that occur. Drones have come down drastically in price, and could lead to all sorts of creative, novel studies like the ones mentioned! Be creative, think local - chances are a study you have in mind has not been done before, especially in rural settings. Check with your local town hall for records of what has and has not been done, do something original!
  • Drones can be used to study water flow patterns of local or regional areas, particularly for crops, nurseries, protected areas and nature reserves, and other areas of interest that require any controlled or regulated water flow for irrigation and/or drainage. Much research has been done on optimal irrigation patterns, for instance. But, if your local region has different landscapes, soil, plant species or crops, weather patterns, rotation of crops that require different water yields, or anything else that is different from previous studies, then you have a novel problem to research! Irrigation and water flow is an ongoing, never-ending process that is important to farming communities in particular, and something like this could develop into a natural long-term research project for teachers and their classes from year to year, where entire databases and studies are done. For any long-term studies, changes in patterns due to erosion, storms, snow and ice deformations to the landscape, and other geological features could also be relevant. Schools might contact state universities or water agencies to get ideas or become partners in studies. 
  •  Included in the drone studies could be ongoing chemical analyses of soil and/or any water sources within the defined ecosystem. Could also include biological studies of soil and water sources, for example doing counts of different insects and organisms within the sample. Do these measurements change over time? If so, what is driving the changes? Teachers could develop a robust, long-term research program around this type of work.